You have a different point of view. The world in which I spent my employment time (which is where most people are likely spend theirs), as well as my experience with clients during my 25 years in business as a consultant, proprietary and commercial were essentially one in the same, and that's how most lay people would understand it. Free open source, GNU/Linux, however you would like to label any aspect of that particular world, and the inane number of licenses as well as the distinction between them and all their many iterations, were non existent. Such software were viewed as unsafe, unacceptable, and a PIA to track and/or explain during a compliance audit. And for many, "free" was an absolute no-no and not allowed - period. If you pay for something, though, regardless its nature, then that's acceptable. The terms and conditions of the purchase or subscription are clear and concise, and different from those of "free" software. If it's paid, the seller is obligate (to one extent or another) - if it's free then they are not. Perhaps not absolutely, but close enough to be.

Redhat would be considered acceptable because you have to pay for a subscription. If you pay for something, it has to be safe - at least, that's how lay people look at it.

And as far as most (certain) businesses are concerned? If you pay for it, it's proprietary, If you don't pay for it, then it's free, and if it's free then there has to be a catch, or it's been concocted by a hacker, or it will blow up your systems, steal your firstborn - it's evil incarnate and grounds for expulsion.

In any case such as above, the distinction between proprietary and commercial just isn't acknowledged. It rolls like this - if it is commercial it isn't free, if it's proprietary it isn't free. Interchangeable in their eyes. And free open source is not a thing, and certainly not allowed. There are exceptions to every rule, but I did not have a single client that allowed free open source software. You either paid for an onsite license, or you paid for subscription user licenses. The particulars of the licensing didn't matter, at least not in their minds. And if you were caught breaking with compliance, you were in deep trouble, or got walked out the door.

My clients had no idea that I used GNU/Linux and free open source software - most probably would have sent me packing if they knew. Had they understood, of course, what any of that was in the first place. Only IT would understand something like that - and IT was always a woefully overworked minority. The staff making the decisions on what software systems to purchase or subscribe to, nothing they would consider was open source. And sadly enough, the people I sold systems to, there was nothing available open source that existed which was powerful enough or could meet most of their needs in one system without having to add on this, that or the other thing. Even then nothing even come close to proprietary,

So - terminology can be subjective, even when it comes to apples and oranges. But, that's just my take. That I have retained my sanity in any measure after all my years in business is purely a wonder.

Sorry - think I went off the rails a bit there, lol...